Burner control indicator



Aug. 9, 1966 P. J. ECKELBERRY ET AL BURNER CONTROL INDI CATOR Filed Nov. 5, 1965 THERMOSTAT l4 LINE VOLTAGE E 5 BURNER CONTROL LINE VOLTAGE WITH FLAME I3\. DETECTION AND SAFETY LOCKOUT PILOT VALVE IGNITION INVENTOR. PATRICK J. ECKELBERRY FREDERICK H. LOY

ATTORNEY United States Patent 3,265,112 BURNER CONTROL INDICATOR Patrick J. Eckelberry, Minneapolis, and Frederick H. Loy,

Miunetonka, Minn., assignors to Honeywell Inc., Minneapolis, Minn., a corporation of Delaware Filed Nov. 5, 1965, Ser. No. 506,467 9 Claims. (Cl. 158-28) Our invention is concerned with a burner control indicator which is utilized to provide a memory of the particular sequence of a fuel burner unit wherein a failure to establish flame or a flame failure has occurred. We accomplish this by the use of an output means which is characterized as output means requiring an initiating voltage to trigger the output means and which, after being triggered, is maintained by a maintaining voltage.

7 Referring to the single figure, a schematic showing of our invention, reference numeral 10 identifies a conventional burner control having a flame detection portion and a safety lockout portion. This flame detector may be of the type disclosed in the Fred T. Deziel US. Patent 3,023,803, issued March 6, 1962, which is assigned to the assignee of the present invention. The structure of the Deziel patent utilizes a low voltage thermostat and a jumper 11 is provided to short the low voltage thermostat terminals. Reference numerals 12 and 13 identify power input terminals adapted to be connected to conductors 20 and 21 and to a source of AC. line voltage, terminal 12 being connected through line voltage thermostat 14. Thermostat 14 is adapted to be located in an area to be heated by operation of fuel burner unit 15. While we have shown a temperature sensitive control 14, this control may be sensitive to other conditions created by operation of fuel burner unit 15, or may be a manual start-stop station.

For purposes of simplicity, we have shown fuel burner unit 15 diagrammatically and indicate by reference numeral 16 the pilot valve portion of the fuel burner unit, by reference numeral 17 the ignition portion, and by reference numeral 18 the main valve portion.

As disclosed in the above-mentioned patent, burner control 10 includes a terminal 19 which is effective to energize main valve 18 from the line voltage conductors 20 and 21 when a pilot flame has been detected. Terminal 22 of the burner control is adapted to be connected to ignition 17 and to energize the ignition upon a need for operation of the fuel burner unit, as evidenced 'by the closing of thermostat 14. Reference numeral 23 of the burner control is adapted to be connected to pilot valve 16 to energize the pilot valve upona need for operation of the fuel burner unit.

-In the construction shown in the above-mentioned patent, ignition 17 is de-energized upon the detection of pilot flame. It may be desirable to maintain the ignition energized, in which case the ignition is connected to terminal 23.

The apparatus thus far described is a conventional control arrangement whereby a burner control is connected, under the control of a thermostat, to energize a fuel burner unit to establish a trial-for-ignition period and, if ignition is successful, to establish a run period. During the trial-for ignition period, the pilot valve and ignition are energized. If pilot flame is established, the flame detection portion of the burner control is effective to energize the main valve, and thus establish the running period.

Our invention is concerned with a means of monitoring the above operation to provide a memory type indication of the particular sequence of the fuel burner unit in which a failure to establish flame or a flame failure has occurred.

We accomplish this by a plurality of output means including utilization means in the form of neon indicator lights 30, 31 and 32. These neon indicator lights are characterized as output means which have a high initiating voltage requirement and a lower maintaining voltage requirement. That is, once the neon indicators are fired by a higher voltage, they can be maintained in an energized condition by a lower maintaining voltage.

Reference numeral 33 identifies generally a source or maintaining voltage which provides a positive terminal 34 and a negative terminal 35, this voltage being regulated by a zener diode and the source of maintaining voltage being connected to line voltage conductors 29 and 21 through thermostat 14, such that the thermostat is adapted to apply a source of maintaining voltage to the neon indicators, through diodes, only so long as there is a need for operation of the fuel burner unit. The source of maintaining voltage is not effective to initially fire the neon indicators.

The neon indicators are fired by a plurality of diode poled circuit means 40, 41 and 42 which connect the neon indicators to terminals 19 and 23. Specifically, neon indicator 30 is connected to terminal 23 to apply an initiating voltage to the indicator at the beginning of the trial-for-ignition period, when pilot valve 16 is energized. Neon indicators 31 and 32 have an initiating voltage applied thereto when voltage is applied to terminal 19 to energize main valve 18, this signalling the beginning of the running period of the fuel burner unit. Time delay means is provided in the form of capacitor 43 to delay the initiating of the indicator 32.

Considering the operation of the apparatus, it will be assumed that thermostat 14 closes to indicate the need for operation of fuel burner unit 15. Energizing voltage 1s then applied to terminal 23 to connect pilot valve 16 across conductors 20 and 21; energizing voltage is applied to terminal 22 to connect ignition 17 across conductors 20 and 21; and an initiating voltage is applied to indicator 30 to energize this indicator.

If there is a failure to establish a pilot flame, burner control 10 will go out on safety lockout to de-energize terminals 22 and 23. However, thermostat 14 remains in a condition calling for operation of fuel burner unit 15 and the source of maintaining voltage 34-35 remain-s operative to maintain the indicator 30 energized, thus indicating that 'burner control 10 went out on safety lockout in an attempt to establish ignition during the trial-for-ignition period.

Normally, a pilot flame is established and the flame detector within burner control 10 is effective to energize terminal 19. Energization of terminal 19 connects main valve 18 across conductors 20 and 21 and likewise connects both indicators 31 and 32 across conductors 20 and 21. Indicator 31 is immediately energized. If the pilot flame is detected only momentarily and the main flame is not established the main valve would be energized only for the period during which flame was proven. Then operating volt-age is quickly removed from terminal 19 (due to operation of the flame detector within control 10) and, due to the time delay means 43, indicator 32 is not energized. However, thermostat 14 remains in a condition calling for operation of fuel burner unit 15 and, in this case, both indicators 30 and 31 remain energized to indicate that the burner control went out on safety lockout as aresult of failure to establish the flame at the beginning of the running period.

Normally, however, the pilot flame is effective to light off the main flame and, after a short time delay, for example 25 seconds, indicator 32 is energized. Subsequently, if a flame failure is experienced, the burner control goes out on safety lockout to remove voltage from terminals 19, 22 and 23, and indicators 30, 31 and 32 remain energized to indicate that the burner control went 63 out on safety lockout during the run period of the fuel burner unit.

If no flame failure is experienced, then at the end of a need for operation of the fuel burner unit, thermostat 14 opens to de-energize all components of fuel burner unit 15 and to remove the source of maintaining voltage 3435 from the indicators, causing them to be de-energized and restoring the apparatus to the condition wherein the apparatus may recycle on the next call for operation of the fuel burner unit.

The circuits which apply a source of initiating voltage to the indicators and the circuits which apply a source of sustaining voltage to the indicators each include diode means, poled to isolate terminals 19, 22 and 23 of the burner control and the source of maintaining voltage 3435 from each other.

In a particular embodiment of our invention, the source of sustaining voltage 34-35 had a magnitude of 91 volts, resistors 60 and 61 had a magnitude of 100,000 ohms, resistors 62, 63 and 64 had a resistance of 15,000 ohms, resistor 65 had an impedance of 10 meg ohms, and capacitor 43 had a capacitance of .2 microfarad.

We claim as our invention: 1. In apparatus comprising a burner control and means responsive to the need for operation of a fuel burner unit, the burner control having first electrical terminal means adapted to be connected to the fuel burner unit and to have voltage applied thereto to institute a trial-for-ignition period upon a need for operation of the .fuel burner unit, and having second electrical terminal means adapted to be connected to the fuel burner unit and to have voltage applied thereto to institute a run period upon the establishment of ignition;

first output means including utilization means and having an initiating voltage and a maintaining voltage,

first circuit means connecting said first output means to the burner control second electrical terminal means to apply an initiating voltage to said first output means when a voltage is applied to the second electrical terminal means,

a source of maintaining voltage,

and second circuit means connected to be controlled by the means responsive to the need for operation of the fuel burner unit and to apply said source of maintaining voltage to said first output means only so long as there is a need for operation of the fuel burner unit.

2. The apparatus of claim 1, including, second output means including utilization means and having an initiating voltage and a maintaining voltage, wherein said first circuit means connects said second output means to the burner control first electrical terminal means to apply an initiating voltage to said second output means when a voltage is applied to the first electrical terminal means,

and wherein said second circuit means applies said source of maintaining voltage to said second output means only so long as there is a need for operation of the fuel burner unit.

3. The apparatus of claim 2 wherein said first and second output means are first and second neon devices.

4. The apparatus of claim 2 wherein said source of maintaining voltage is regulated, and wherein said second circuit means connects said source of maintaining voltage to said first and second output means, and connects said source of maintaining voltage to an energizing source upon a need for operation of the fuel burner unit.

5. The apparatus of claim 2 wherein said first circuit means and said second circuit means include diode means poled to isolate the burner control first and second elec trical terminal means and said source of maintaining voltage from each other.

6. The apparatus of claim 2, including, third output means including utilization means and having an initiating voltage and a maintaining voltage, wherein said first circuit means connects said third output means to the burner control second electrical terminal means, wherein said second circuit means applies said source of maintaining voltage to said third output means only so long as there is a need for operation of the fuel burner unit, and wherein time delay means is provided to delay the initiation of said third output means.

7. The apparatus of claim 6 wherein said first, second and third output means are first, second and third neon devices, wherein the initiating voltage and the maintaining voltage are DC voltage, and wherein said time delay means is a capacitor connected in parallel with said third neon device.

8. The apparatus of claim 6 wherein said first, second and third output means are first, second and third neon devices and wherein said first circuit means and said second circuit means include diode means poled to isolate the burner control first and second electrical terminal means and said source of maintaining voltage from each other.

9. The apparatus of claim 1 wherein said first output means is a first neon device and wherein said first circuit means and said second circuit means include diode means poled to isolate the burner control second electrical terminal means and said source of maintaining voltage from each other.

References Cited by the Examiner UNITED STATES PATENTS 3,150,709 9/1964 Bolmgren 158-28 JAMES W. WESTHAVER, Primary Examiner, 

1. IN APPARATUS COMPRISING A BURNER CONTROL AND MEANS RESPONSIVE TO THE NEED FOR OPERATION OF A FUEL BURNER UNIT, THE BURNER CONTROL HAVING FIRST ELECTRICAL TERMINAL MEANS ADAPTED TO BE CONNECTED TO THE FUEL BURNER UNIT AND TO HAVE VOLTAGE APPLIED THERETO TO INSTITUTE A TRIAL-FOR-IGNITION PERIOD UPON A NEED FOR OPERATION OF THE FUEL BURNER UNIT, AND HAVING SECOND ELECTRICAL TERMINAL MEANS ADAPTED TO BE CONNECTED TO THE FUEL BURNER UNIT AND TO HAVE VOLTAGE APPLIED THERETO TO INSTITUTE A RUN PERIOD UPON THE ESTABLISHMENT OF IGNITION; FIRST OUTPUT MEANS INCLUDING UTILIZATION MEANS AND HAVING AN INITIATING VOLTAGE AND A MAINTAINING VOLTAGE, 